Project Summary Abstract Patients with thalassemia major require regular red cell transfusions to circumvent their deficient or absent production of globin. As a consequence of these lifelong transfusion programs, affected patients have an intense and sustained exposure to blood-borne pathogens and may be a sentinel population for the recognition of new infectious agents in the blood supply. Regular transfusion programs also lead to other transfusion-related complications including red cell alloimmunization and iron overload. The latter is a particularly devastating complication of therapy and requires regular chelation therapy to prevent widespread organ damage and early death from cardiac failure or arrhythmias. Previously, the CDC- sponsored [unreadable]Prevention of Complications of Iron Overload[unreadable] developed a multi-center study of transfusion- related and other complications of thalassemia. The present study offers an opportunity to continue the regular collection of relevant clinical, demographic and genetic data to address the major goals of characterizing and preventing the complications of thalassemia. Using a variety of strategies and tools, The Thalassemia Program of the Children's Hospital of Philadelphia will continue to enroll patients in the surveillance projects, establish methods for consumer input and assess and meet the needs of unserved or underserved populations, provide multi-disciplinary, comprehensive care, identify patients with newly acquired transfusion-transmitted infections and other disease-related and treatment-related complications, and disseminate the study findings. In addition, our Thalassemia Program has identified two areas of new investigation: (1) the use of the longitudinal cohort to characterize the current mortality of patients with thalassemia major and differences in mortality related to treatment in or outside of a treatment center and (2) defining the current risk of postsplenectomy events, in particular sepsis and thrombosis. Overall, these studies will better define the optimal therapy of thalassemia and will also contribute to improvements in the treatment of other disorders requiring regular red cell transfusions. Project Narrative By characterizing in detail the complications of thalassemia, the proposed studies will not only improve the management of this inherited blood disorder but will also influence the treatment of all patients requiring short-term and long-term red cell transfusion programs.